Summary of NACI advice on vaccination with COVID-19 vaccines following myocarditis (with or without pericarditis)

Abstract

On January 14, 2022, the Public Health Agency of Canada (PHAC) released updated guidance from the National Advisory Committee on Immunization (NACI) in the COVID-19 vaccine chapter of the Canadian Immunization Guide, on the topic vaccination following myocarditis and pericarditis. This chapter includes NACI’s recommendations on the use of COVID-19 vaccines up to and including January 14, 2022.
Rare cases of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the heart lining) following vaccination with COVID-19 mRNA vaccines have been reported in Canada and internationally. Most cases have occurred in males 12 to 29 years of age after a second dose of an mRNA vaccine. Most cases have been mild and resolved quickly.
Following review of the latest evidence and consultation with Canadian cardiologists, NACI has issued updated guidance on re-vaccination with COVID-19 vaccines for those who experienced myocarditis and/or pericarditis after a previous dose of an mRNA COVID-19 vaccine.
Since June 2021, NACI has recommended that people who experienced myocarditis and/or pericarditis after a first dose of an mRNA COVID-19 vaccine should wait to get their second dose until more information was available.